go-ceph/internal/timespec/timespec.go
John Mulligan 29ebb61850 timespec: add a helper function to convert from Timespec to C
Signed-off-by: John Mulligan <jmulligan@redhat.com>
2021-01-12 14:47:30 +00:00

40 lines
986 B
Go

package timespec
/*
#include <time.h>
*/
import "C"
import (
"unsafe"
"golang.org/x/sys/unix"
)
// Timespec behaves similarly to C's struct timespec.
// Timespec is used to retain fidelity to the C based file systems
// apis that could be lossy with the use of Go time types.
type Timespec unix.Timespec
// CTimespecPtr is an unsafe pointer wrapping C's `struct timespec`.
type CTimespecPtr unsafe.Pointer
// CStructToTimespec creates a new Timespec for the C 'struct timespec'.
func CStructToTimespec(cts CTimespecPtr) Timespec {
t := (*C.struct_timespec)(cts)
return Timespec{
Sec: int64(t.tv_sec),
Nsec: int64(t.tv_nsec),
}
}
// CopyToCStruct copies the time values from a Timespec to a previously
// allocated C `struct timespec`. Due to restrictions on Cgo the C pointer
// must be passed via the CTimespecPtr wrapper.
func CopyToCStruct(ts Timespec, cts CTimespecPtr) {
t := (*C.struct_timespec)(cts)
t.tv_sec = C.time_t(ts.Sec)
t.tv_nsec = C.long(ts.Nsec)
}